1. Field of the Invention
The present invention relates to high-speed graphical display systems. In particular, the present invention relates to high-speed graphical display systems with touch screen input capability.
2. Discussion of the Related Art
Modern computers interact with the human user over many data input and data output devices. One particularly effective form of data output to a human user is through a visual means, such as a graphical or video display monitor (e.g., LCD display monitor). In many applications the graphical display solicits data input from the human user. In that regard, it is a particularly effective form of data input from the human user when the input capability is integrated with the graphical display, so that the human user can provide the solicited data input in the context of the displayed image. A tactile (“touch”) system is one such data input device. In a tactile system, a touch-sensitive surface is overlaid onto a graphical display monitor, so that the human user can indicate the data to be input by touching the display monitor using his/her fingers in the context of the image displayed. For example, the human user may indicate scrolling of a displayed page of text by running a finger down the touch-sensitive surface, along the side of the graphical display. Contact with the touch-sensitive surface sends a stream of data (i.e., tactile responses of the touch-sensitive surface, primarily positions detected over time) to the application program running on a host computer which provides the displayed image. The application program then interprets the data stream to determine the data input.
In the prior art, a graphical display with a touch screen capability interfaces with the host computer through two separate interfaces. Typically, one interface with the host computer is a graphical or video data interface (e.g., DVI-D or any or various forms of VGA interface), while the other interface with the host computer is the tactile device interface. The tactile device interface is typically provided by the universal serial bus (USB) or a proprietary interface specified by the manufacturer of the tactile system. As a result, because two sets of cables are required, the interface costs are high and the footprint of the touch-capable graphical display is large also.